Why am I seeing unknown user bounces from AOL when some emails are delivered?
Summary
What email marketers say11Marketer opinions
Email marketer from Litmus says regularly cleaning your list of unengaged users or hard bounces helps improve deliverability, protecting you from being marked as spam.
Email marketer from Email Geeks shares that they saw some bounces that looked like a "we're turning off old accounts" kind of situation, spiked yesterday but normal otherwise. Then clarifies that Laura's comment is the right one.
Email marketer from Mailjet explains that bounces can be either soft or hard. A hard bounce, such as 'User Unknown', indicates a permanent reason, but sometimes servers delay the hard bounce notification.
Email marketer from Sendgrid recommends cleaning your email list regularly to remove inactive or invalid addresses to minimize bounces and maintain a good sender reputation. Deliverability can vary based on list hygiene.
Email marketer from Stackoverflow suggests that intermittent delivery followed by bounces could indicate the recipient server is having temporary issues, accounts are being closed or are reaching quota limits.
Email marketer from Email Geeks responds that bounces might indicate AOL is turning off old accounts and seeing that activity spiked.
Email marketer from Email on Acid suggests that unknown user bounces can result from typos, inactive accounts, or users intentionally blocking the sender.
Email marketer from Validity explains that it's important to stay current with best practices when sending email to different providers such as AOL, and to monitor inbox placement and bounce rates to identify deliverability trends.
Email marketer from Email Geeks explains that if a user blocks a sender, AOL sends a user unknown bounce.
Email marketer from Reddit shares that AOL frequently purges inactive accounts. Some emails may still be delivered if the account is recently inactive, while others might bounce immediately.
Email marketer from Postmark notes that senders should review feedback loops from providers such as AOL to respond appropriately to issues. This includes bounce processing.
What the experts say2Expert opinions
Expert from Email Geeks explains that if a user blocks a sender, AOL sends a user unknown bounce.
Expert from Spamresource suggests that AOL may be more aggressive in deactivating accounts, and these deactivated accounts may cause bounce-back issues, even if some emails are delivered.
What the documentation says3Technical articles
Documentation from RFC defines '550 5.1.1 User unknown' as an error signifying that the recipient mailbox doesn't exist on the server.
Documentation from Mailhardener explains that a 550 error (often associated with 'User Unknown') means the email server couldn't find the mailbox you tried to deliver to. This can be due to a typo, domain issue or the user has been removed.
Documentation from AOL Help indicates that a 'User Unknown' error signifies the recipient address doesn't exist, could be misspelled, or the account is inactive.
Related resources0Resources
No related resources found.